Just like so many things here (resorts - dive operators - fishing guides - etc.) we all have our preferences and for different reasons. I started with Tropic and have not had a problem so I stick with them.
Here's my hint though: If there are two or more people coming in to international I have them take a taxi to the muni airport. It costs half as much to fly from muni as it does from international. The taxi ride used to be BZ$40 but the guests that just came it said it had been raised (because of the cost of gas) to BZ$45. Still a good buy.
I like them to see a bit of the main land and everyone has always raved about the education they get from the cab driver. Most of my friends come in on American and arrive at 3:42. I book them for the 4:30 flight out of muni. If they miss that, and none have so far, they will be put on the 5:30 flight.
It is not uncommon for them to get on the flight which, when not full, goes to international and picks up the overflow. That is always good for a laugh! The other good thing about this is that their luggage is always on the same plane that they are on. Not so coming from international. I came in on the 4:30 flight but my luggage didn’t get here until the 530 one. It’s a good thing I have become a Belizean and know how to wait.